Known urea sensor systems are generally used in tanks for urea solutions such as diesel exhaust fluid (DEF) for diesel engines. The fluid sensors are used for monitoring certain properties of the urea solution in order to analyze the quality of the solution. However, certain circumstances may negatively influence the measurements. The urea solution tends to create bubbles during movement of the solution, for example, during filling of the urea tank. These bubbles may influence measurements of the fluid sensor. Particles formed by debris or frozen urea solution may also disturb measurements of the fluid sensor.